Centrifugal fuze



Jan. 29, 1963 D. E. CRAIG 3,075,465

CENTRIFUGAL F'UZE Filed July 23, 1957 2 Sheets-Sheet 1 INVETOR. Do/mw E.CRn/6.

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Jan. 29, 1963 D. E. CRAIG 3,075,465

CENTRIFUGAL FUZE Filed July 23, 1957 2 Sheets-Sheet 2 United Statesarent tice 3,975,465 CEN'I'RFUGAL FUZE Donald E. Craig, Fort Wayne,Ind., assigner to rEhe llt/Iagnavox Company, Fort Wayne, Ind., acorporation Filed .lilly 23, 1957, Ser. No. 675,794 1 Claim. (Cl.H12-76.2)

This invention relates generally to a fuze device and more particularlyto a fuze adapted to arm a missile or projectile after a predetermineddelay period following the time of launching of the missile orprojectile.

The principal object of this invention is to provide a fuze for missilesor projectiles which is responsive to forces created by the rotationalmovement of the missile or projectile after it is launched for arming adetonator.

Another object of this invention is to provide a fuze for a missile orprojectile which is adapted to operate an electrical circuit or anarming mechanism of any other suitable type after the lapse of apredetermined time period from time of launching the missile orprojectile.

Still another object of this invention is to provide a fuze for amissile or projectile which has an arming mechanism operable after acertain time period has elapsed after the time of launching the missileor projectile and which includes a mechanism for creating such delaywhich is substantially unaffected by temperature, humidity, mechanicalshock or the like.

In accordance with this invention there is provided a fuze for a missileor projectile comprising an arming mechanism, means responsive to forcescreated by rotation by said missile or projectile after it is launchedfor actuating said arming mechanism, a trigger device adapted to releasesaid force responsive means when said missile or projectile is launched,and means cooperating with said trigger device and said force responsivemeans for timing the movement of said force responsive means andproviding a delay period between the initiation of its movement and itsactuation of said arming mechanism.

The full nature of the invention will be understood from theaccompanying drawings and the following description and claim:

FIG. 1 is -a top plan view of the fuze provided in accordance with thisinvention;

FIG. 2 is a cross-section taken on line 2 2 of FIG. l;

FIG. 3 is a front elevation of the device illustrated in FIG. l;

FIG. 4 is a rear elevation of FIG. l;

FIG. 5 is a side elevation taken from the right-hand side of FIG. 1;

FIG. 6 is a detailed perspective view of the conductor supportinginsulator utilized in the fuze illustrated in FIG. l; and

FIG. 7 is a detailed front elevation of the structure shown in FIG. 6together with top and bottom insulators cooperating therewith.

rl'he fuze as provided in accordance with this invention comprises abase member 111 adapted to be mounted in a missile or projectile rwithits longitudinal axis corresponding generally with the longitudinal axisof the missile or projectile. The arming mechanism of the fuze may beelectrical or mechanical, but for purposes of illustrating thisinvention a portion of an electrical arming mechanism consisting of aiilamentary or foil-like conductor 11 is shown in electrical contactwith the rod-like electrical terminals 12 and 114. Conductor 11 may besupported on a central insulating member 1S and extend over its uppersurface, over a retainer linger 15a, and downwardly across the endthereof to form a severable portion at 16. The remainder of conductor 11may be laid along the lower surface of insulator 15 over retainerlingers 15b and 15e and joined to the end of the terminal 14.

The terminals 12 and 14 are mounted within suitable bores in the base 10as illustrated in FIG. 5. The inner end of terminal 12 projects throughcentral insulator 15 to its upper side, as at 12a while the inner end ofterminal 14 extends only to the lower side of insulator 15, as at 14a.rl`he outer ends of terminals 12 and 14 project outwardly of base 10 toprovide terminal portions which may be connected electrically with adetonator in the conventional fashion. Terminals 12 and 14 areillustrated from base 1li by cylindrical insulators 17. In order toinsulate conductor 11 from the base 1li, top and bottom insulators 18and 19 are placed above and below the central insulator 1S. For holdingthe members 12, 14, 15, 18 and 19 in position, there is provided a cover20 which may be fastened to the base lll by means of suitable machinescrews 21.

The arming mechanism is actuated by a rotor 23, rotatably mounted in thebase 1li by means of a pin 24 one end of which is nested within a bore25 in base 10, the other end of which extends into bore 26 of a rotorcover 2li. Cover 2S may be secured to the base 10 by a plurality ofmachine screws 29 threaded into bores 30 in the base 10 and engagingshoulder portions 31 formed in cover 28 by cutting out the cover as at32. Rotor 23 has a notch 34 extending approximately 90 around itsperiphery whereby the end portion 15a' of insulator 15 may extendinwardly beyond the outer periphery of the rotor 23.

At one end of notch 34, a knife 37 of insulating material is mountedwith its cutting edge facing into the cut-out portion. The knife 37 maybe fastened to rotor 23 in any suitable manner, but for purposes ofillustration it is shown as having a shank 38 within which is mounted apin member 39, the outer ends of which cooperate with bores in the rotorto hold the knife in place. Notch 34 unbalances rotor 23 so thatrotation of the missile or projectile will cause rotor 23 to rotaterelative to base 10 and move knife 37 toward the severable portion 16 ofconductor 11. Insulator 15 is grooved at 15e so that knife 37 may enterthis groove to cut conductor 11 at 16 and effect arming of the missileor projectile. In this manner, the arming mechanism and the rotorstructure act as an electrical switch.

For normally holding the rotor 23 in a safe position, there is provideda trigger mechanism in the form of slide 41, one end of which is heldwithin a notch 42 formed on the periphery of rotor 23 by means of a leafspring 43 positioned within a recess 44 formed in the base 1t) adjacentthe outer end of slide 41. For holding slide 41 and spring 43 inoperative position, there is provided a cover 4S fastened by means ofscrews 46.

rI`he yslide 41 is normally locked with its inner edge engaging notchy42 of rotor 23 by means of a set-back pin 48. Pin 48 is arranged withits longitudinal axis in parallel with the longitudinal axis of the fuzeand missile so that accelerative forces at the time of launching of themissile or projectile will dislodge pin 48 from engagement with slidey41, thereby unlocking slide 41 so that it can respond to rotativeforces created by rotation by the missile or projectile and move out ofnotch 42 against the force created by spring 43.

Pin 48 is prevented from moving in response to normal shock forces bymeans of a coil spring y49 (FIG. 4) supported within a slot 50 on ashaft 51 mounted within the base 1G. Spring 49 has an end portion 52bearing on the outer end of pin 4S. The other end 53 of spring 49 islocked within a slot 54 in base 10. Normal shock forces are insuiicientto flex portion 52 of spring 49 but acceleration forces on pin 48 createsufficient force on portion 52 to iiex the spring 49 thereby to permitpin 4 to move out of engagement with slide 41.

For controlling the speed of rotation of rotor 23, there are provided anumber of glass beads 56 disposed within a cut-out portion 57 on theperiphery of rotor 23 and confined within this space by rotor cover 28and the wall portions of base 10 which surround the rotor. The slide 41moves outwardly in' response to rotative forces of the missile orprojectile far enough to create a gap between the Wallv58 of rotor 23and the end of slide 41 which engages within notch 42. The beads maythen escape at a, certain rate' through the restricted passage betweenthe end of slide 41 and wall 58 thereby causing rotor 23 to rotate at apredetermined speed. This predetermined speed of rotation provides adelay period after the missile isired and'before knife 37 can cut theconductor 11. In operation, the set-back pin 48y ilexes spring 49 andmoves out of engagement with the slide or trigger 41 in response. to anacceleration force created when the missile or projectile is launched.The rotative forces which occur immediately after the missile orprojectile is launched, caused the slide 41 to move outwardly toward theperiphery of the base 10' against the retarding force of spring 43. Thismovement of slide 41 opens a slot between the walls of notch 42 and thewall 58 of'cut-out portion 57 on the periphery of`rotor 23. Rotation ofa missile or projectile also causes counter-rotationof rotor 23'in-a-counter-clockwise direction, for example.

'Therefore the beads 56 are forced through the slot between the endofslide 41 and the walls 42 and 58. The width ofthe slot and the forcesAtending to rotate rotork 23 determine the rate of ow of the beadsthrough the slot. This rate of flow in turn determines the amount oftime required for rotor 23 to rotate from the-position shown'in FIG. 1to aposition wherefknife37 engages the loop'16 offconductor 11".- Afterthis predetermined time' interval, knife 37r will cut conductor 11,thereby to arm the detonatingmechanism of the missile or projectileafter the missile or projectile has travelled along its trajectory'for acertain distance.

From the foregoing description, it will be apparent that this inventionprovides a mechanism having a relatively simple structure with a smallnumber of parts for providing a delay period before the detonator of themissile or projectile is armed after launching. The mechanism issubstantially unaffected by temperature, humidity, shock or other'conditions, whereby it is safe during shipment or other handling anduntilV after it has f been launched.

missile or projectile whereby it is responsive to forces, Y

created by rotation of said missile or projectile after it is launched,said disk including a notch, a trigger device releasable by launchingforces and comprisingr a slide mounted in said base for movementVrelative to said base out of said notch to form` a slot and a. set-backpin disposed longitudinally of said base and engaging said slide,l

said disk including a` cut-out portion on its peripheryy forming acontinuation of said notch and filled with small beads whereby rotationkof said disk is controlled by ow of said beads through the sloty betweensaidy slide and the walls of said notch.

References Cited in the tile of this patent- UNITED STATES PATENTS896,135 Meigs et al Aug. 18, 1908 2,485,817 Dike Oct. 25, 1949 2,737,890Erode Mar. 13, 1956 2,750,889 Kuhn June 19, 1956 2,825,284 Kuhn Mar. 4,1958Vv 2,971,463 Burrell Feb. 14,1961.

